P_[ACTION]_shared#

Concurrent access to a common file by all participating processes, with a shared file pointer. See the basic definitions and a schematic view of the pattern below.

P_[ACTION]_shared Definition#

Property

Description

Measured pattern

As symbolized in figure I/O benchmarks, aggregation for output

Elementary I/Oaction

As symbolized in the figure below. In this figure, Nproc is the number of processes.

MPI routines for theblocking mode

MPI_File_write_a t/MPI_File_read_at

MPI routines for thenonblocking mode

MPI_File_iwrite_at /MPI_File_iread_at

etype

MPI_BYTE

File type

MPI_BYTE

MPI data type

MPI_BYTE

Reported timings

t (in μsec) as indicated in the figure I/O benchmarks, aggregation for output, aggregate and non-aggregate for the Write flavor.

Reported throughput

x/t, aggregate and non-aggregate for the Write flavor

P_[ACTION]_shared Pattern#

../_images/image16.png